A liquid crystal display panel is generally formed by laminating a color filter substrate and an array substrate, wherein a liquid crystal layer is encapsulated in the space between the two substrates. Because a liquid crystal molecule itself does not emit light, the display requires a light source to display an image. According to different types of light sources employed, liquid crystal display may be divided into transmissive liquid crystal display, reflective liquid crystal display and transflective liquid crystal display.
Among of them, for a transmissive liquid crystal display, it mainly employs a back light source as the light source, a back light source is set behind the liquid crystal panel, and pixel electrodes on the array substrate are transparent electrodes, which act as a transmissive region, thus it is favorable for the light from the back light source to penetrate through the liquid crystal layer to display an image; for a reflective liquid crystal display, it mainly employs a front light source or an external light source as a light source, and its array substrate employs reflecting electrodes that are formed of a metal or other materials with a good reflection feature as a reflective region, which is suitable for reflecting a light from the front light source or the external light source; and for a transflective liquid crystal display, it may be regarded as a combination of a transmissive liquid crystal display panel and a reflective liquid crystal display panel, wherein not only a reflective region, but also a transmissive region is set on the array substrate, and a back light source and a front light source or an external light source may be utilized at the same time for displaying.
A transmissive liquid crystal display has an advantage that a bright image can be displayed in a dark environment, but it also has a disadvantage that the transmitted light only occupies a small proportion of the light emitted by its back light source, and the utilization of the back light source is not high; in order to increase the display brightness, the luminance of the back light source needs to be increased greatly, thus the energy consumption is very high.
A reflective liquid crystal display has an advantage that sunlight or a front light source may be employed as a light source and the power consumption is relatively low, but it has a disadvantage that an image cannot be displayed in a dark place due to its dependence on an external light source.
A transflective liquid crystal display has the advantages of both transmissive and reflective liquid crystal display panels, it can not only display a bright image in a dark environment, that is, it can be used indoors, but also be used outdoors. Thus, it is widely used in the display equipment of portable mobile electronic products, for example, mobile products such as mobile phone, digital camera, palmtop and GPRS, etc.
Moreover, in the prior art, in order to improve the display quality of a liquid crystal display, that is, to realize a higher contrast ratio, a quicker response time and a wider viewing angle, a blue-phase liquid crystal material with a rapid response feature gains attention gradually. Blue phase is a liquid crystal phase between isotropic state and cholesteryl phase, the temperature range in which it exists is very narrow, being only a temperature span of about 1° C. However, in recent years, it has been found that the temperature range in which blue-phase liquid crystal exists is widened greatly after it is stabilized by a macromolecule, and it can basically meet the application temperature range as a liquid crystal display material. As the most potential next-generation display, the blue-phase liquid crystal display has the following characteristics: 1) blue-phase liquid crystal is isotropic in the case that no voltage is applied, and a blue-phase liquid crystal display has the characteristics of large visual angle and good dark state; 2) theoretical response time of a blue-phase liquid crystal display may reach millisecond level and below, so that the response time may be improved greatly; 3) due to the excellent stability of blue-phase liquid crystal after being stabilized by a macromolecule, it is isotropic in the case that no voltage is applied, so that it does not require an alignment layer that is indispensable for other various liquid crystal display modes, so that the manufacturing cost can be lowered, and the manufacturing process can be simplified.
For the existing transflective liquid crystal displays, positive liquid crystal is generally employed, an alignment layer is required, and the cell gap of the reflective region is not equal to that of the transmissive region, and the display visual angle needs to be increased.